BAF BLOCKER: In normal embryonic stem cells (top panel), the chromatin remodeling complex esBAF moves nucleosomes into enhancer-flanking DNA regions (blue) to keep enhancers (red) free of nucleosomes so they can promote transcription of protein-coding genes. When esBAF is absent (lower panel), nucleosomes move out of the flanking regions and into the enhancer, freeing up noncoding RNA transcription that begins in the enhancer and continues into the flanking DNA.© SCOTT LEIGHTON
The paper
S.J. Hainer et al., “Suppression of pervasive noncoding transcription in embryonic stem cells by esBAF,” Genes & Development, 29:362-78, 2015.
To stuff more than six feet of DNA into the nucleus of each cell in our body, the genome winds tightly around a core of eight histone proteins, creating structures called nucleosomes that, in turn, are densely packed into chromatin. To transcribe genetic information from DNA to RNA, nucleosomes must be shifted out of the way, a task performed in some cases by the embryonic stem cell chromatin remodeling complex esBAF. This process opens up not just the region of DNA to be transcribed, but promoters and enhancers that encourage transcription.
Recent genome-sequencing work has revealed that enhancer regions not only promote the ...
